Depleted power reserve

[swatch]

I have had a non-Rolex watch serviced only to find that the power reserve is very small, and I have a friend who has a GMT whose power reserve stopped after a service.

What typically causes power reserve issues? Is it the oil used on the movement and spring?

[Vanessa CW21]

The lack of winding causes the power reserve to be small.
Most people have a bad understanding about this working of the watch, but let me give you an example.

Let's say your watch stopped after being off your wrist for a couple of days. Instead of winding it manually for about 40 turn, you shake it a little to make it to start running. You put it on your wrist and have a normal active working day. The watch, since it wasn't prpoerly wound when you put in on, will now be trying to keep running all day, and is literaly trying to catch up with itself all day. So when you take your watch off at night, the mainspring won't be wind very much because all the movement that caused the mainspring to wind a little is already used during those moments in the day you weren't moving (like when you were watching the evening news or checking TRF).
Because there isn't a good amount of winding left on the mainspring, it will now die quickly.

A good way to check if your watch winds sufficiently on the wrist, is when you have an automatic winder at home, to put your watch on there with the stem pulled out (so the movement cannot run) for about 8 hours. Then take your watch off, start the movement (by pushing in the crown), put it down somewhere and see how long it takes before the watch dies. If it takes at least 32 hours, your winding mechanism works great, if it dies soon or doesn't start at all, it time for a trip to your watchmaker!

[doc_colton]

I have that problem with my Submariner, wind it 40 times, wear it 3 or 4 days then take it off and find it's stopped overnight. RSC Toronto checked it and said they couldn't find anything wrong. So maybe I'm not active enough. I'll try your procedure Vanessa. I'm assuming you should let the watch fully run down before putting it on the winder with the stem pulled out.

[swatch]

Originally Posted by Vanessa

The lack of winding causes the power reserve to be small.
Most people have a bad understanding about this working of the watch, but let me give you an example.

Let's say your watch stopped after being off your wrist for a couple of days. Instead of winding it manually for about 40 turn, you shake it a little to make it to start running. You put it on your wrist and have a normal active working day. The watch, since it wasn't prpoerly wound when you put in on, will now be trying to keep running all day, and is literaly trying to catch up with itself all day. So when you take your watch off at night, the mainspring won't be wind very much because all the movement that caused the mainspring to wind a little is already used during those moments in the day you weren't moving (like when you were watching the evening news or checking TRF).
Because there isn't a good amount of winding left on the mainspring, it will now die quickly.

A good way to check if your watch winds sufficiently on the wrist, is when you have an automatic winder at home, to put your watch on there with the stem pulled out (so the movement cannot run) for about 8 hours. Then take your watch off, start the movement (by pushing in the crown), put it down somewhere and see how long it takes before the watch dies. If it takes at least 32 hours, your winding mechanism works great, if it dies soon or doesn't start at all, it time for a trip to your watchmaker!

These are being fully wound. Its as thought the watches have turned from automatic to manual since servicing (maybe the movements were replaced!).

[watchmaker]

Assuming like you said, that your watch is fully wound, the most common cause of lack of power reserve is 'Mainspring Creep'.

Creep is where the mainspring when wound abouve halfway, cannot grip the barrel wall properly, and it slowly (sometimes very quickly) unwinds itself. This is possible because, as has been pointed out in other threads, that a mainspring in an automatic watch is not fixed to the barrel.

Common causes of this are; The wrong strength spring has been installed. or. The barrel wall has been incorrectly lubricated.

When it does run, do you find it gains time? This is another side effect caused by creep.

[cody p]

Originally Posted by watchmaker

Assuming like you said, that your watch is fully wound, the most common cause of lack of power reserve is 'Mainspring Creep'.

Creep is where the mainspring when wound abouve halfway, cannot grip the barrel wall properly, and it slowly (sometimes very quickly) unwinds itself. This is possible because, as has been pointed out in other threads, that a mainspring in an automatic watch is not fixed to the barrel.

Common causes of this are; The wrong strength spring has been installed. or. The barrel wall has been incorrectly lubricated.

When it does run, do you find it gains time? This is another side effect caused by creep.

interesting, i guess the watch would gain time because balance wheel amplitude would drop due to less force pushing the drive train along?

[Tools]

You need to define the problem better...

Power Reserve is how long the watch runs after it is fully wound...

So, are you saying that you fully wind the watch, and then it doesn't last long, or are you saying that it essentially stops when you take it off..

If you wind it fully, and it runs for 40 hours, then it is possible that the auto-wind mechanism isn't functioning correctly.

[Vanessa CW21]

Originally Posted by doc_colton

I have that problem with my Submariner, wind it 40 times, wear it 3 or 4 days then take it off and find it's stopped overnight. RSC Toronto checked it and said they couldn't find anything wrong. So maybe I'm not active enough. I'll try your procedure Vanessa. I'm assuming you should let the watch fully run down before putting it on the winder with the stem pulled out.

You assumed right, sorry I forgot to mention that!

[Lol-x]

Interesting topic, especially mainspring creep as I have a TAG chronometer automatic winding that seems to stop after a few days, I wind it up and it goes again.

It can't be due to lack of wrist activity as all my Rolex watches never suffer this problem.

The power reserve just gets depleted. and double

[doc_colton]

In my case when it's fully wound it runs for about 40 hrs, and does not gain time. I think I'll try the winder trick when it runs down.